Effects of Precipitation on Yield and Water Consumption of Winter Wheat in Loess Plateau in Recent 40 Years
Winter wheat is an important ration crop in the Loess Plateau and the yield is greatly affected by rainfall and other factors,in order to study the effect of precipitation on water consumption and yield of winter wheat,the long-term observation data of winter wheat Zhenyuan experimental site of the Gansu academy of agricultural sciences in recent 40 years were collected.The variation trend of winter wheat yield and water consumption with precipitation was illustrated.The results showed that the yield of winter wheat on the loess plateau increased at a rate of 51.2 kg·hm-2 every year in the past 40 years,but the persistence coefficient was only 0.43.The yield greatly increased with the rise of precipitation from mid-October to mid-November,the first ten days of mid-March,the first ten days of May,and the last ten days of May.The satisfaction rate of precipitation in the whole growth period was 64.4％,but was only 52.7％in the dry year,while at jointing-filling stage was the lowest among different growth stages.The average water consumption during the growth period of winter wheat was 361.3 mm,which showed a downward trend in the past 40 years.The water consumption from sowing to rejuvenation accounted for 34.3％of the total in the whole growth period.In dry years and median water years,the precipitation satisfaction rates were 36.9％at the seedling emergence-jointing stage and 42.2％at jointing-filling stage,respectively.At these 2 stages,precipitation had a significant impact on the yield of winter wheat.According to the yield correlation of winter wheat,the order from high to low was water consumption＞panicles＞grains per ear＞soil moisture before sowing＞precipitation during growth period＞annual precipitation.Winter wheat yield in the loess plateau area had been poorly stable in recent 40 years due to a large proportion of water consumption from sowing to the regreening stage and insufficient precipitation at this time,affected the tillering and spike formation and water use efficiency of winter wheat.Above results indicated that ensuring the precipitation satisfaction rate of winter wheat in the key growth period and the efficient accumulation of precipitation in the fallow period was an important guarantee for stable and high yield of winter wheat,which were of great significance to the sustainable development of winter wheat industry.
国家科技期刊平台
NSTL
万方数据
